Artificial snow production



Mafch 12, 1968 G. F. LE Bus ul, ET AL 3,372,872

ARTIFICIAL SNOW PRODUCTION FiledJuly 26. 196e 2 sheets-s heet l ATTORNEYS March 12, 1968 G. F. LE Bus m, ET Az. 3,372,872

ARTIFICIAL SNOW PRODUCTION Filed July 26, 1966 2 Sheets-Sheet 2 ATTORNEYS United States Patent Office 3,372,872 Patented Mar. 12, 1968 3,372,872 ARTIFICIAL SNGW PRODUC'HUN George F. Le Bus ill, 1801 Ems Road W., Fort Worth,

Tex. 76116; James L. Le Bus, 1525 Melody, Wichita Fals, Tex. 76302; and George F. Le Bus, Jr., Gen.

Del., Taos, N. Mex. 87571 Filed July 26, 1966, Ser. No. 567,967 6 Claims. (Cl. 239-2) Our invention relates generally to artificial snow production and in particular to apparatus and methods which produce artificial snow in improved and advantageous manners.

Previously, a number of systems have been developed for artificially producing snow for application to ski slopes in the event natural snow fall is insufficient. One of the most commonly used techniques is to utilize an air compressor to inject air under pressure into a stream of water immediately upstream from a nozzle to atomize the water in an attempt to produce small particles of moisture which freeze when sprayed into winter atmospheres. The particle size of the moisture should be minimized to avoid the production of sleet-like particles that are unsatisfactory for preferred skiing conditions, While such prior techniques enable the production of relatively small particle sizes, improvements are nonetheless needed since there are a number of disadvantages associated with this technique, some of which derive from the need for using an air compressor. Air compressors of suitable capacity are expensive and maintenance costs high; however, they have been needed for their ability to produce relatively small particle sizes. We have originated artificial snow production apparatus and methods which produce artificial snow having small particle sizes, which decrease equipment costs, and which provide relatively troublefree service and other advantages, some of which will be explained subsequently.

It is accordingly, the general object of our invention to provide improved methods and apparatus for manufacturing artificial snow for ski slopes, for example.

Another object of our invention is to provide improved means for manufacturing artificial snow through utilization of water in two different thermodynamic states in a manner which creates turbulence, small particle sizes, and good particle density and distribution.

Another object of our invention is to provide nozzle means for mixing liuids in a manner that improves the density and distribution of water particles in the production of artificial snow.

These and other objects are effected by our invention as will be apparent from the following description taken in accordance with the accompanying drawings, forming a part of this application, in which:

FIG. l is a perspective view illustrating a ski slope having apparatus installed thereon for producing artificial snow in accordance with the principles of our invention;

FIG. 2 is a schematic and fragmentary perspective view of apparatus which may be used in connection with that shown in FIG. 1; and

FIG. 3 is a fragmentary perspective view of a preferred form of dispensing installation or outiet station which may be used in combination with the system of FIG. l.

Referring now to FlG. 1, numeral 11 designates a ski slope having disposed along the length thereof a hot water circulation line 13 (which in this instance is in the form of a loop) and a cold water circulation line 15 (also a loop in this instance), both of which communicate with a stationary power station 17. Preferably the power station is located on a downward region of the slope in the vicinity of the control and power apparatus 19 of the ski lift 21. A water supply line 23 extends to a water supply 25 which may be a nearby lake or pond or a water well.

At selected locations along the hot water and cold water circulation lines are a plurality of outlet stations 27 which introduce by subsequently described means particles of moisture into the atmosphere where they are frozen and distributed across the slope as indicated in FIG. l. A preferred construction for each outlet station 27 will `be described hereinafter in connection with FIG. 3.

Power station 17 communicates with water supply line 23 through a master control valve 29. A portion of the water received from the supply line may be introduced to a high pressure water pump 31 via a conduit 33 having a control valve 35 interposed therein. Water is forced by pump 31 into a steam generator or boiler 37 via another conduit 39. Hot water from the generator or boiler 37 enters and leaves the steam circulation loop line through output conduit 41 and return conduits and valves 40, 42. A three-way valve d3 is connected with the output conduit 41 and line 13 to enable circulation of a controlled quantity of the hot water in the clockwise or counterclockwise directions.

The reference to the line or loop 13 as the hot water line does not restrict our invention to the use of hot water in the liquid state; rather, our invention encompasses the use of hot water in the form of liquid or steam. Preferably, the hot water is maintained in the liquid state by the proper relationship of pressure and temperature. lf, for example, the pressure in line 13 exceeds about 100 p.s.i. and the temperature exceeds about 338 Fahrenheit, the hot water will remain liquid and may be referred to as being superheated. if the pressure falls below about p.s.i. or 338 Fahrenheit, the hot water will be transformed to steam. As will become more fully apparent hereinafter, our invention is operative with the hot water in either form.

Another portion of the water received by the system through water supply line 23 communicates with another high pressure pump l5 via a conduit 47 having a valve 49 interposed therein. An outlet conduit 53 communicates between the pump 45 and the cold water circulation line 15, as does a pair of return conduits and valves 51, 52. Outlet conduit 53 and loop 15 are connected with a three-way control valve 55 therein to control the volume and direction of flow to the cold water circulation line 15.

Thus, the power station 17 illustrated schematically in FIG. 2 may be used to conveniently supply cold water and hot water to the respective circulation lines. The steam generator or lboiler 37 should be capable of supplying `hot water at a temperature in a range from at least about 250 to 300 Fahrenheit at a pressure range of at least about 400 to 500 psi. The volume of steam generated should be sufiicient to enable each outlet station 27 to eject into the atmosphere from about four to five gallons per minute of hot water.

High pressure water pump 45 `and the water supply 25 should be capable of supplying water to the cold water supply loop 15 at temperatures from preferably about 40 to 50 Fahrenheit and pressures from preferably about 400 to 500 p.s.i. for economic operation. The volume of water supplied shoul-d be sufhcient to enable 20 to 25 gallons per minute of cold water to be ejected from each outlet station 27 into the atmosphere. To insure that the water in the system does not freeze, outlets (not shown) are provided to drain the various lines. Also, the lines are buried beneath the frost line and preferably insulated to minimize heat transfer between the lines and the ground.

The pressures specified above are sufiicient to overcome the hydrostatic head of the wate-r in the circulation lines 13 and 15 and enable the discharge of water at suitable pressures from each of a reasonable number of outlet stations 27 if placed on a slope having about a 500 ft. elevation over that of the power station 17. The diameter of lines 13, 15 should be sufficient to minimize asusta llui-:l frictional pressure drops. The maximum permissible pressures are determined by economics, since equipment costs increase significantly with increased pressure.

A preferred construction of outlet station 27 is illustrated in FIG. 3. The cold water circulation line l and the hot water circulation line 13 extend beneath a housing 57. The housing contains a pair of substantially vertically extending conduits 59, 61 which communicate respectively with the cold water circulation line 15' and the hot Water circulation line 13. The conduits 59, 61 have quick-connect couplings 63, 65 that are adapted to receive a respective and a preferably llexiblc conduit 67, 69. The upper ends of the flexible conduits 67, 69 communicate with an injection chamber 71 which is upstream from a diverging nozzle outlet 73. Valve means (preferably coupled with pressure regulators) 75, 77 are interposed in the vertical conduits 59, 61 and valve control means 79, 81 extend to a position above the upper surface of the housing 57 to enable control over the relative amounts of hot and cold water fed into injection chamber 7l. A

pedestal 83 is used to support the injection chamber 7l and the diverging nozzle outlet 73 in a manner to permit automatic or manual oscillation thereof through a range of generally 60 to enable complete coverage of the slope, as is indicated in FIG. l.

The injection chamber-nozzle structure described above may have a number of forms and our invention in its broadest aspects is not limited to specific nozzle constructions. However, it is advantageous to aerate the cold water as it is mixed with `the steam for greater improvement of particle size and distribution. This result may be accomplished by forming passages in the nozzle housing from the flow channel to the atmosphere to draw air into the nozzle by `a resulting suction effect.

In operation, water is introduced from water supply through master control valve 29 and control valves 35, 49 into high pressure pumps 331., 45. Cold water circulation line 15 is fed by high pressure pump 45 and the volume and direction of flow circulating through the line l5 is controlled by the valves 5l, 52 and 55. The temperature of the Water introduced into and circulating through circulation line 15 is maintained at a relatively low temperature, preferably in the range previously specified.

Simultaneously, Water is pumped through high pressure pump 31 into the steam generator or boiler 37, which introduces `hot water through conduit di and valve 43 to the hot water circulation line 13 in the range of temperature, pressure and volume previously specified. Valves 4l), 42 and 43 are used to control the Volume of steam circulating through line 13.

At each outlet station 27, the valve means 7S, 77 and valve control means 79, 8l control the relative amounts of hot and cold Water owing into injection chamber 7l. The mixture of the relatively cold water and the high temperature hot Water generates turbulent oW and line particles of moisture. When the hot, superheated Water enters the atmosphere, it immediately turns to steam to further produce turbulence and small particles. The density of the particles may be controlled by use of the valve control means 79, 81 and, if desired, the production of snow from each outlet station may be ceased.

l-t should be apparent from the foregoing that we have provided an invention having significant advantages. The mixture of hot Water, which turns to steam under atmospheric pressure, and cold Water at the outlet nozzle of cach outlet station produces small particle sizes of uniform distribution which are then forced into the freezing atmosphere. As they drift to the surface of the slope, they collect thereon in a manner that closely simulates natural snowfall. This natural looking snowfall is ac-hieved in a manner which eliminates the need for expensive, and occasionally t-roublesome compressors. The utilization of a steam generator greatly decreases the initial installation cost and provides a system having apparatus which is significantly free of maintenance problems. Moreover, the utilization of water and steam in the manner previously described enables the provision of a dense concentration of line particles and thereby decreases the time required to cover a slope.

While we have shown our invention in only one of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

We claim:

il. Apparatus for producing artificial snow, said apparatus comprising: a cold water circulation line extending along a predetermined area; a hot `water circulation line extending along the slope generally adjacent the cold water line; means for inducing and maintaining the ow of hot water in said hot water line; means for inducing the flow of cold water in said cold Water circulation line; and nozzle means at selected outlet locations along said lines and connected with each line to mix the hot and cold Water and disperse the mixture into :the atmosphere,

'ith said hot Water having a pressure and a temperature that results in the formation of steam at least when the hot Water is ejected into the atmosphere.

2. The apparatus dened by claim 1 wherein said hot Water is superheated Water having a pressure of at least about p.s.i. and a temperature of yat least about 338 Fahrenheit.

3. The invention dened by claim 1 wherein said nozzle means includes a cold Water nozzle having at least one passage that extends from the ow channel of the nozzle means to the atmosphere to :aerate the cold water preparatory to mixing with said hot water.

4. A method for producing artificial snow, said method comprising: heating one supply of water to a temperature and maintaining a pressure thereon to insure the formation of steam, at least when the pressure is suddenly reduced to atmospheric; pumping said heated Water and a supply of cold Water in separate conduits to selected outlet locations; mixing said hot and cold Water with suitable nozzle means, while simultaneously discharging the mixture into the atmosphere and onto a selected ground area.

5. The method defined by claim 4 wherein said hot water is superheated Water having a pressure of at least 100 p.s.i. and a temperature of at least 338 Fahrenheit.

6. The method defined by claim 4 wherein said nozzle means includes a cold Water nozzle having at least one passage `that extends from the flow channel of the nozzle means to the atmosphere to aerate the cold Water preparatory to mixing with said hot Water.

References Cited UNlTED STATES PATENTS EVERETT W. KIRBY, Primary Examiner, 

4. A METHOD FOR PRODUCING ARTIFICIAL SNOW, SAID METHOD COMPRISING: HEATING ONE SUPPLY OF WATER TO A TEMPERATURE AND MAINTAINING A PRESSURE THEREON TO INSURE THE FORMATION OF STEAM, AT LEAST WHEN THE PRESSURE IS SUDDENLY REDUCED TO ATMOSPHERIC; PUMPING SAID HEATED WATER AND A SUPPLY OF COLD WATER IN SEPARATE CONDUITS TO SELECTED OUTLET LOCATIONS; MIXING SAID HOT AND COLD WATER WITH SUITABLE NOZZLE MEANS, WHILE SIMULTANEOUSLY DISCHARGING THE MIXTURE INTO THE ATMOSPHERE AND ONTO A SELECTED GROUND AREA. 